Risk of lymphoma after renal transplantation varies with time: an analysis of the United States Renal Data System

Post-transplant malignancy: Focusing on virus-associated etiologies, pathogenesis, evidence-based management algorithms, present status of adoptive immunotherapy and future directions

Modern immunosuppression has led to a decrease in rejection rates and improved survival rates after solid organ transplantation. Increasing the potency of immunosuppression promotes post-transplant viral infections and associated cancers by impairing immune response against viruses and cancer immunoediting. This review reflects the magnitude, etiology and immunological characteristics of various virus-related post-transplant malignancies, emphasizing the need for future research. A multidisciplinary and strategic approach may serve best but overall literature evidence targeting it is sparse. However, the authors attempted to provide a more detailed update of the literature consensus for the prevention, diagnosis, management and surveillance of post-transplant viral infections and associated malignancies, with a focus on the current role of adoptive immunotherapy and the way forward. In order to achieve long-term patient and graft survival as well as superior post-transplant outcomes, collaborative research on holistic care of organ recipients is imperative.

Lymphoproliferative disorders after renal transplantation along 2 decades: a large longitudinal study of 21.546 recipients

INTRODUCTION

Post transplant lymphoproliferative disorders (PTLD) are heterogeneous lymphoid proliferations in recipients of solid organs which seem to be related to Epstein Barr Virus (EBV). The use of antilymphocyte antibodies, EBV seronegativity in the recipient,acute rejection and CMV infection have been identified as classical risk factors.

MATERIAL Y METHODS

We have studied in a retrospective observational study, the incidence of PTLD in a period of 22 years, its relationship with EBV, presence of classical risk factors and outcome in 21546 simple adult renal transplant recipients from cadaveric and living donors, transplanted in 21 hospitals from 1990 to 2009.

RESULTS

A total of 275 recipients developed PTLD (1,2%),195 males (70,9%), 80 females (29,1%) aged 59.2 (p25 44.7 p75 68)years. Two hundred forty-five (89.0%) were 1st transplant recipients and 269 (97,8%) from cadaveric donors. EBV in the tissue was reported in 94 out of the 155 studied recipients (60.6%) and 86.0% of the proliferations were due to B lymphocytes. PTLD median appearance after transplant were 42.months (p25, 75, 12, 77, 5). One hundred eighty-eight recipients out of 275 patients (68.3%) had any classical risk factor and the use of antilymphocyte antibodies was the most frequent. During the follow-up, 172 patients died (62,5%) and 103 (37,5%) had a complete remission. The main cause of death was PTLD progression (n = 91, 52,9%), followed by sepsis (n = 24, 13,9%). The follow-up period post-transplant of the recipients was between 3 and 22 years. The incidence was 0,14% during the first year post-trasplant and 0.98% the cumulative incidence at 10 years. Patient survival after diagnosis was 51%, 44% and 39% after 1, 2 and 5 years, respectively. Finally, overall graft survival was 48%, 39% and 33% at the same periods.

CONCLUSION

PTLD has a low incidence in renal transplant recipients. Most of the proliferations are due to B lymphocytes and seem to have a close relationship with EBV. PTLD can develop in the absence of classical risk factors. The prognosis is poor, mainly due to PTLD progression, but the survivors can even maintain their grafts.

Extremely delayed-onset post-transplant lymphoproliferative disorder in a renal transplant patient

Post-transplant lymphoproliferative disorder (PTLD) is a rare condition that occurs in patients who have undergone solid organ transplantation. Symptoms at presentation depend on the organs involved. PTLD most commonly occurs in the first year after transplant (early onset) or around 5 years after transplant (late onset). Herein, we report a rare presentation of central nervous system PTLD in an adult who presented with seizures 17 years after renal transplantation. After extensive infectious and transplant-related workup, brain biopsy confirmed the diagnosis of PTLD. The patient was treated with rituximab and high-dose methotrexate. Eighteen months later, the patient had no signs of recurrence. Very late-onset (>10 years) PTLD is rare, but is likely to become more common with more long-term survivors of solid organ transplant. Data are limited but show that the factors associated with very late-onset PTLD are different from early or late-onset PTLD.

Incidence and Outcomes of Early Cancers After Kidney Transplantation

Outcomes of early cancers after kidney transplantation are not well-understood. We included recipients of first live and deceased donor kidney transplants who developed de novo cancers in Australia and New Zealand between 1980-2016. We compared the frequency and stage of specific cancer types that developed early (≤12-months) and late (>12-months) post-transplantation. Risk factors for death were evaluated using multivariable Cox regression analyses. Of 2,759 recipients who developed de novo cancer, followed-up for 40,035 person-years, 243 (8.8%) patients were diagnosed with early cancer. Post-transplant lymphoproliferative disease, urinary cancers and melanoma were the most common cancer types (26%, 18%, and 12%) and the majority were either in-situ or locally invasive lesions (55%, 84%, and 86%). Tumors arising early from the gastrointestinal and respiratory systems were uncommon but aggressive, with 40% presenting with metastatic disease at time of diagnosis. Overall, 32% of patients with early cancers died within a median of 4.7 months (IQR:0.6-16) post-diagnosis and 91% were cancer-related deaths. Older recipient and donor age were associated with an increased risk of all-cause death. Early cancers, though infrequent in kidney transplant recipients, are associated with poor outcomes, as nearly 1 in 3 died from cancer-related death; with majority of deaths occurring within 12-months of cancer diagnosis.

Targeted Delivery of BZLF1 to DEC205 Drives EBV-Protective Immunity in a Spontaneous Model of EBV-Driven Lymphoproliferative Disease

Epstein-Barr virus (EBV) is a human herpes virus that infects over 90% of the world's population and is linked to development of cancer. In immune-competent individuals, EBV infection is mitigated by a highly efficient virus-specific memory T-cell response. Risk of EBV-driven cancers increases with immune suppression (IS). EBV-seronegative recipients of solid organ transplants are at high risk of developing post-transplant lymphoproliferative disease (PTLD) due to iatrogenic IS. While reducing the level of IS may improve EBV-specific immunity and regression of PTLD, patients are at high risk for allograft rejection and need for immune-chemotherapy. Strategies to prevent PTLD in this vulnerable patient population represents an unmet need. We have previously shown that BZLF1-specific cytotoxic T-cell (CTL) expansion following reduced IS correlated with immune-mediated PTLD regression and improved patient survival. We have developed a vaccine to bolster EBV-specific immunity to the BZLF1 protein and show that co-culture of dendritic cells (DCs) loaded with a αDEC205-BZLF1 fusion protein with peripheral blood mononuclear cells (PMBCs) leads to expansion and increased cytotoxic activity of central-effector memory CTLs against EBV-transformed B-cells. Human-murine chimeric Hu-PBL-SCID mice were vaccinated with DCs loaded with αDEC205-BZLF1 or control to assess prevention of fatal human EBV lymphoproliferative disease. Despite a profoundly immunosuppressive environment, vaccination with αDEC205-BZLF1 stimulated clonal expansion of antigen-specific T-cells that produced abundant IFNγ and significantly prolonged survival. These results support preclinical and clinical development of vaccine approaches using BZLF1 as an immunogen to harness adaptive cellular responses and prevent PTLD in vulnerable patient populations.

Autoimmune encephalitis (NMDAR antibody) in a patient receiving chronic post-transplant immunosuppression

Autoimmune encephalitis associated with antibodies (Abs) directed against the synaptic ligand-gated ion channel NMDA receptor (NMDAR) was first described as a paraneoplastic disorder in association with ovarian teratoma. Other forms of neoplasia have subsequently been reported although many patients do not have a tumour. Tumour removal, where applicable, and immunotherapy form the mainstays of treatment. We present a patient who developed NMDAR-Ab encephalitis despite being chronically immunosuppressed following organ transplantation, and who was eventually found to have an occult malignancy in the form of non-Hodgkin's lymphoma.

Contribution of solid organ transplant recipients to the pediatric non-hodgkin lymphoma burden in the United States

BACKGROUND

Pediatric solid organ transplant recipients have a 100 to 200 times higher risk of non-Hodgkin lymphoma (NHL) than the general pediatric population. Consequently, transplant-related NHL may contribute considerably to the pediatric NHL burden in the United States.

METHODS

A cohort study using a linkage between the US transplant registry and 16 cancer registries was conducted. Cancer incidence rates were calculated for people less than 20 years old in the transplant and general populations. Rates were applied to transplant registry and US census data to estimate pediatric NHL counts for transplant recipients and the general population.

RESULTS

During 1990-2012, an estimated 22,270 NHLs were diagnosed in US children and adolescents; they included 628 cases diagnosed in transplant recipients. Thus, 2.82% of pediatric NHL diagnoses in the general population (95% confidence interval [CI], 2.45%-3.19%) occurred in transplant recipients. Among transplant recipients, the most common subtypes were diffuse large B-cell lymphoma (DLBCL; 64.5% of cases) and Burkitt lymphoma (BL; 8.6%). For DLBCL and BL, transplant recipients contributed 7.62% (95% CI, 6.35%-8.88%) and 0.87% (95% CI, 0.51%-1.23%) of diagnoses, respectively. The proportion of NHLs that occurred in transplant recipients was highest among children less than 5 years old (4.46%; 95% CI, 3.24%-5.69%) and in more recent calendar years (3.73% in 2010-2012; 95% CI, 2.07%-5.39%). DLBCL patterns were similar, with transplant recipients contributing 19.78% of cases among children less than 5 years old (95% CI, 12.89%-26.66%) and 11.4% of cases in 2010-2012 (95% CI, 5.54%-17.28%).

CONCLUSIONS

Among children and adolescents, solid organ transplant recipients contribute a substantial fraction of NHL diagnoses, particularly DLBCL diagnoses. This fraction has increased over time. Prevention efforts targeted toward this group could reduce the overall pediatric NHL burden. Cancer 2017;123:4663-4671. © 2017 American Cancer Society.

A retrospective analysis of post-transplant lymphoproliferative disorder following liver transplantation

OBJECTIVE

To evaluate response rates and survival in adults developing post-transplant lymphoproliferative disorder (PTLD) following liver transplantation.

METHODS

Patients were identified retrospectively and data collected through local liver and haematology electronic databases and pharmacy records.

RESULTS

Forty-five patients were identified. The median age at first transplant and at development of PTLD was 48 and 54 years, respectively, with the median time from transplant to PTLD diagnosis of 56 months. The majority of cases (76%) were monomorphic B-cell lymphomas, and 36% of tumours were EBV positive. Treatment involved reduction in immune-suppression (RIS) in 30 (67%) with RIS the only treatment in 3. Ten (22%) patients were treated with rituximab alone, 13 (29%) with chemotherapy alone and 14 (31%) patients were treated with rituximab and chemotherapy. Twenty-six (58%) patients achieved a complete response (CR). At a median follow-up of 27 months, the median overall survival (OS) was 50 months. Response and OS were not associated with clinical factors or the use of rituximab.

CONCLUSION

Outcomes reported in this study are favourable and comparable to those reported previously. The addition of rituximab did not appear to have improved outcomes in this series, although a significant proportion of patients were able to avoid chemotherapy.

Cancer Risk After Pediatric Solid Organ Transplantation

BACKGROUND

The effects of pediatric solid organ transplantation on cancer risk may differ from those observed in adult recipients. We described cancers in pediatric recipients and compared incidence to the general population.

METHODS

The US transplant registry was linked to 16 cancer registries to identify cancer diagnoses among recipients <18 years old at transplant. Standardized incidence ratios (SIRs) were estimated by dividing observed cancer counts among recipients by expected counts based on the general population rates. Cox regression was used to estimate the associations between recipient characteristics and non-Hodgkin's lymphoma (NHL) risk.

RESULTS

Among 17 958 pediatric recipients, 392 cancers were diagnosed, of which 279 (71%) were NHL. Compared with the general population, incidence was significantly increased for NHL (SIR = 212, 95% confidence interval [CI] = 188-238), Hodgkin's lymphoma (SIR = 19, 95% CI = 13-26), leukemia (SIR = 4, 95% CI = 2-7), myeloma (SIR = 229, 95% CI = 47-671), and cancers of the liver, soft tissue, ovary, vulva, testis, bladder, kidney, and thyroid. NHL risk was highest during the first year after transplantation among recipients <5 years old at transplant (SIR = 313), among recipients seronegative for Epstein-Barr virus (EBV) at transplant (SIR = 446), and among intestine transplant recipients (SIR = 1280). In multivariable analyses, seronegative EBV status, the first year after transplantation, intestine transplantation, and induction immunosuppression were independently associated with higher NHL incidence.

CONCLUSIONS

Pediatric recipients have a markedly increased risk for many cancers. NHL constitutes the majority of diagnosed cancers, with the highest risk occurring in the first year after transplantation. NHL risk was high in recipients susceptible to primary EBV infection after transplant and in intestine transplant recipients, perhaps due to EBV transmission in the donor organ.

Epstein-Barr virus and renal transplantation

Epstein-Barr virus (EBV) is a gamma herpesvirus associated with diseases ranging from asymptomatic viremia to post-transplant malignancies in kidney transplant recipients. EBV specifically is associated with post-transplantation lymphoproliferative disorder (PTLD), in kidney transplant recipients, with increased risk in EBV seronegative patients with EBV seropositive donors on intensified immunosuppression. The diagnosis of PTLD relies on clinical suspicion plus tissue biopsy with polymerase chain reaction (PCR) testing of blood currently used for risk determination in high-risk recipients. Therapeutic strategies for PTLD include reduction of immunosuppression, chemotherapy and rituximab, and consideration of sirolimus-based immunosuppression. Antivirals such as ganciclovir are used to prevent reactivation of cytomegalovirus and other herpes viruses but are not onco-therapeutic. Radiation therapy or surgery is indicated for bulky, disseminated or recalcitrant disease. Prognosis varies depending on the type of malignancy identified and stage of disease.

Lymphoproliferative disorders in inflammatory bowel disease patients on immunosuppression: Lessons from other inflammatory disorders

Immunosuppressive agents, such as thiopurines, methotrexate, and biologics, have revolutionized the treatment of inflammatory bowel disease (IBD). However, a number of case reports, case control studies and retrospective studies over the last decade have identified a concerning link between immunosuppression and lymphoproliferative disorders (LPDs), the oncological phenomenon whereby lymphocytes divide uncontrollably. These LPDs have been associated with Epstein-Barr virus (EBV) infection in which the virus provides the impetus for malignant transformation while immunosuppression hampers the immune system’s ability to detect and clear these malignant cells. As such, the use of immunosuppressive agents may come at the cost of increased risk of developing LPD. While little is known about the LPD risk in IBD, more is known about immunosuppression in the post-transplantation setting and the development of EBV associated post-transplantation lymphoproliferative disorders (PTLD). In review of the PTLD literature, evidence is available to demonstrate that certain immune suppressants such as cyclosporine and T-lymphocyte modulators in particular are associated with an increased risk of PTLD development. As well, high doses of immunosuppressive agents and multiple immunosuppressive agent use are also linked to increased PTLD development. Here, we discuss these findings in context of IBD and what future studies can be taken to understand and reduce the risk of EBV-associated LPD development from immunosuppression use in IBD.

Epstein-Barr virus: dermatologic associations and implications: part II. Associated lymphoproliferative disorders and solid tumors

Epstein-Barr virus (EBV) was the first human virus to be associated with oncogenesis. Over the past few decades, cumulative research has revealed that latent EBV infection may be implicated in the pathogenesis of a heterogeneous group of lymphoproliferative disorders and malignancies occurring in both immunocompetent and immunocompromised hosts. Many of these diseases have either primary or secondary cutaneous manifestations. Serologic studies and EBV-encoded RNA in situ hybridization stains have been used to show the association of EBV with disease; while these findings may imply a role, they do not equate with causation. In part II of this continuing medical education review, the salient features of EBV-associated lymphoproliferative disorders and solid tumors are detailed.

Steroid withdrawal in renal transplantation

Over the last decade, steroid minimization became one of the major goals in pediatric renal transplantation. Different protocols have been used by individual centers and multicenter study groups, including early and late steroid withdrawal or even complete avoidance. The timing of steroid withdrawal determines if antibodies are used, as avoidance and early withdrawal require antibody induction, while late withdrawal typically does not. A monoclonal antibody was used in most protocols during an early steroid withdrawal together with tacrolimus and mycophenolate mofetil in low immunological risk patients. Polyclonal induction was reported as effective in high-risk patients. Cyclosporine A and mycophenolate mofetil were used in late steroid withdrawal with no induction. All described protocols were effective in terms of preventing acute rejection and preserving renal graft function. There was no superiority of any specific protocol in terms of clinical benefits of steroid withdrawal. Pre-puberty determined growth benefit while other clinical advantages, including better control of glycemia, lipids, and blood pressure, were age independent. It is not clear whether the steroid withdrawal increases the risk of recurrence of primary glomerular diseases post-transplant, however it cannot be excluded. There is no evidence to date for a higher risk of anti-HLA production in steroid-free children after renal transplantation. Key summary points--Current strategies to minimize the steroid-related adverse effects in pediatric renal graft recipients include steroid withdrawal, early or late after transplantation, or complete steroid avoidance--Early steroid withdrawal or avoidance is generally used following the induction therapy with mono- or polyclonal antibodies, while in late steroid withdrawal induction therapy was generally not used- Elimination of steroids (early or late) does not increase the risk of acute rejection and does not deteriorate long-term renal graft function- Early steroid withdrawal is possible in patients at high immunological risk using a combination of polyclonal antibody induction, tacrolimus, and mycophenolate mofetil- All protocols of steroid minimization showed relevant clinical benefits, however the growth-related benefit was limited to pre-pubertal patients in all but one of the studies- Adverse events of steroid withdrawal occurred in a higher incidence of post-transplant bone marrow suppression Key research points - There is no clear evidence of the impact of steroid withdrawal on the risk of recurrence of primary glomerulonephritis after renal transplantation in children, therefore further evaluation of this important issue should be performed in prospective trials- There is limited pediatric data on the risk of anti-HLA/donor-specific antibody production in steroid-free patients after renal transplantation. It is not clear whether the selection of the type of induction antibody (lymphocyte depleting versus short, two-dose administration of anti-IL2R inhibitor) is important in this term. The production of anti-HLA antibodies should then be monitored on a regular basis and analyzed in prospective trials.

The Seville expert workshop for progress in posttransplant lymphoproliferative disorders

: Posttransplant lymphoproliferative disorders (PTLDs) are associated with significant morbidity and mortality among solid-organ transplant patients, but approaches to diagnosis and management vary considerably. An international multidisciplinary panel evaluated current understanding of risk factors and classification systems and developed recommendations to aid in PTLD prevention. We considered evidence on PTLD risk factors including Epstein-Barr virus serostatus and immunosuppression and identified knowledge gaps for future research. Recommendations address prophylactic and preemptive strategies to minimize PTLD development, including modulation of immunosuppression and antiviral drug regimens. Finally, new classification criteria were outlined that may help facilitate standardized reporting and improve our understanding of PTLD.

Posttransplant malignancies in renal transplant recipients: 22-years experience from a single center in Pakistan

OBJECTIVE

To study the incidence, types and distribution pattern of malignant tumors in renal transplant recipients at a single center in Pakistan.

MATERIALS AND METHODS

This retrospective study was conducted at Sindh Institute of Urology and Transplantation (SIUT) and included all transplant patients on regular follow-up from November 1986 to December 2008. The original biopsy reports and case files of all patients who developed posttransplant malignancies were reviewed and relevant demographic, clinical, radiological, and histopathological data were retrieved and analyzed. SPSS version 10.0 was used for statistical analysis.

RESULTS

Over 22 years of study period, 1816 renal transplants were carried out at our center. Among these, 44 patients developed malignancies constituting an overall incidence rate of 2.4%. All patients in this study were males with a mean age of 34.9±9.5 years (range: 9 to 60 years). The most common type of malignancy was lymphoma (27 patients, 61.4%), followed by Kaposi's sarcoma (11 patients, 25%) and skin malignancies (3 patients, 6.8%). One case each of adenocarcinoma of the gallbladder, acute myeloid leukemia (AML), conjunctival carcinoma-in-situ and seminoma were also diagnosed.

CONCLUSION

Posttransplant malignancies occurring in our renal transplant recipients show different incidence rates and patterns as compared with western studies.

Post-transplantation lymphoproliferative disorder in pediatric kidney-transplant recipients - a national study

PTLD is the most common malignancy in pediatric kidney-transplant recipients. We examined the prevalence, clinical features, and outcome of PTLD in Israel. Twelve (4.4%) of 272 pediatric (<19 yr) kidney-transplant recipients retrieved from a search of the NIKTR for 1991-2008 had acquired PTLD at a median of 3.2 yr post-transplantation. PTLD-affected patients were younger at transplantation (4.2 vs. 12.5 yr, p = 0.02), had a higher rate of OKT3 therapy for acute rejection (25% vs. 4%, p = 0.015), and 5/12 were EBV-seropositive at transplantation. Graft dysfunction was the presenting sign in six (50%). PTLD was predominantly abdominal (83%) and B-cell type (67%); T-cell PTLD occurred exclusively in EBV-seropositive patients. Treatment consisted of immunosuppression cessation (6/12, 50%), antiviral agents (7/12, 58%), anti-CD20 monoclonal antibodies (4/12, 33%), and chemotherapy (6/12, 50%). Survival was 100% in the EBV-naïve patients and 40% in the EBV-seropositive patients. Graft loss occurred in three of eight survivors (37.5%). PTLD-associated mortality risk was older age: 11.2 vs. 3.4 yr, longer dialysis: 15 vs. 6.5 months, T-cell type disease (75%), later PTLD onset: 6.35 vs. 1.9 yr post-transplantation and era of transplantation (43% mortality before vs. 20% after 2001). Pretransplantation EBV-seronegative status might confer a survival benefit with early detected PTLD. EBV-seropositive patients are at risk for aggressive late-onset lethal PTLD.

T-Cell Lymphoma/Sézary Syndrome in a Liver Transplant Recipient

Background:

Cutaneous T-cell lymphoma is a rare subtype of posttransplantation lymphoproliferative disease, with only 29 cases reported in the literature to date, the majority of which are post-renal transplantation. Only a few were reported after pancreas, heart, and bone marrow transplantation. There have been no reports of cutaneous T-cell lymphoma following liver transplantation to date.

Objective:

We report a case of a 76-year-old male who developed generalized eczematous eruption 13 years after a liver transplantation. Investigations showed that it was Epstein-Barr virus-negative, CD3-positive, and CD4-positive cutaneous T-cell lymphoma with Sézary cells in the blood.

Conclusion:

This shows that cutaneous T-cell lymphoma/Sézary syndrome can also develop after liver transplantation. To our knowledge, there are no similar reports in the English literature.

Rehospitalization after kidney transplantation during the first year: length, causes and relationship with long-term patient and graft survival

INTRODUCTION

There is a wide interest in epidemiologic studies assessing different causes of post-kidney transplantation rehospitalization. However, there is a paucity of knowledge on the long-term survival and graft function of rehospitalized kidney transplant recipients during the first year. Knowledge of posttransplant rehospitalization causes may help guide the preventive program at the first year. In our study, we assess causes for hospitalization and investigate the long-term patient and graft survival after non-fatal rehospitalization in kidney recipients during the first year.

MATERIALS AND METHODS

We retrospectively studied the medical histories of 419 kidney transplant recipients whose operations were performed between 1986 and 2009 at Charles Nicolle Hospital, in Tunis, Tunisia. Among these patients, a total of 296 posttransplant rehospitalizations of kidney transplant recipients during the first year occurring in 191 (45.5%) patients were assessed. Clinical characteristics of the patients, including gender, age, reason for kidney failure, weight, height, blood group, length of pretransplant dialysis, immunosuppressive regimen, postoperative complications, the length of hospital stay, transplantation-admission interval, causes of rehospitalizations, graft loss, and mortality rate were reviewed. For donors, these demographics included age, gender, blood group, type of donor (deceased or living), and relationship to the recipient. Because rehospitalizations are possible for more than one cause, the sum of frequencies of rehospitalization causes is more than 100%.

RESULTS

There was 1 rehospitalization in 121 patients, 2 rehospitalizations in 47 patients, 3 rehospitalizations in 15 patients, 4 rehospitalizations in 5 patients, 5 rehospitalizations in 2 patients and 6 rehospitalizations in 1 patient. Rehospitalization was more frequent for diabetic patients without significant association. The causes of rehospitalization were infection in 221 cases (55.5%), renal dysfunction in 106 cases (26%), cardiovascular event in 10 cases (2.4%), and diabetic ketoacidosis in 11 cases (2.7%). The length of hospital stay was 22.5 ± 29.6 days, 20.15 ± 22.16 days, 25 ± 30 days and 23.4 ± 27.5 days, respectively, in the first, second, third, and fifth rehospitalizations. Median hospital stay for all rehospitalizations was between 14 and 16 days. The risk factors of rehospitalization were: use of mycophenolate mofetile (P = .0072), use of cyclosporine (P = .0073), and cytomegalovirus infection (P < .001). There was no significant correlation between rehospitalization and either lost of graft and death.

CONCLUSIONS

During the first year after kidney transplantation, rehospitalization was especially required because of infections and renal dysfunction. The risk factors of rehospitalization were cadaveric graft, use of mycophenolate mofetil, use of cyclosporine, and cytomegalovirus infection. To prevent and minimize rehospitalizations during the first year, a specific preventive program based on infection prevention and graft function monitoring should be established.

Lymphoproliferative disorders after adult kidney transplant: epidemiology and comparison of registry report with claims-based diagnoses

BACKGROUND

Posttransplant lymphoproliferative disorder (PTLD) is a major complication of kidney transplant.

STUDY DESIGN

Retrospective cohort study comparing PTLD incidence rates using US Medicare claims and Organ Procurement and Transplantation Network (OPTN) data, examining risk factors for PTLD in OPTN data, and studying recipient and graft survival after PTLD diagnosis.

SETTING & PARTICIPANTS

All adult first-transplant patients who underwent deceased or living donor kidney-only transplants in 2000-2006 (n = 89,485) followed up through 3 years posttransplant.

PREDICTORS

Recipient and donor characteristics, HLA mismatches, viral serologic test results, and initial immunosuppression.

OUTCOMES

OPTN-reported or Medicare claims-based PTLD diagnosis, recipient and graft survival after OPTN-reported PTLD diagnosis.

MEASUREMENTS

Adjusted HRs for PTLD diagnosis estimated using a Cox proportional hazards model; probability of survival free of all-cause graft failure estimated using the Kaplan-Meier method.

RESULTS

The incidence rate of PTLD during the first posttransplant year was 2-fold higher in Medicare claims (0.46/100 patient-years; 95% CI, 0.39-0.53) than in OPTN data (0.22/100 patient-years; 95% CI, 0.17-0.27). Factors associated with increased rates of PTLD included older age, white race (vs African American), induction with T-cell-depleting antibodies, Epstein-Barr virus seronegativity at the time of transplant, and cytomegalovirus seronegativity at the time of transplant. The adjusted risk of death with graft function was 17.5 (95% CI, 14.3-21.4) times higher after a report of PTLD, and the risk of death-censored graft failure was 5.5 (95% CI, 3.9-7.7) times higher.

LIMITATIONS

Shortcomings inherent in large databases, including inconsistencies in patient follow-up, reporting, and coding practices by transplant centers; insufficient registry data to analyze acute rejection episodes and antirejection treatment; no available data for potential effects of different types of PTLD treatment on patient outcomes.

CONCLUSIONS

Despite the limitations of data collected by registries, PTLD clearly is an important complication; both mortality and death-censored graft failure increase after PTLD.

Early versus late outset of lymphoproliferative disorders post-heart and lung transplantation

BACKGROUND AND OBJECTIVES:

The presentation time of post-transplantation lymphoproliferative disorders (PTLD) are not well described because of the limited number of cases occurring at each center and lack of a reliable and unequivocal classification together with the absence of multi-institutional prospective studies. We gathered information on the histopathological and clinical features and prognosis of the disease in a very large number of heart and lung transplant recipients, with data from 27 previous reports, with an emphasis of time of presentation.

DESIGN AND SETTING:

Retrospective analysis of data for individual patients from published studies, entered into a database and reanalyzed.

METHODS:

A comprehensive review of the literature by PubMed and Google scholar was performed to find all data available reports on PTLD after heart and lung transplantation.

RESULTS:

Data from 288 PTLD patients after heart or lung transplantation from 27 reports were entered into analysis. Heart and lung recipients with early-onset PTLD compared with late-onset PTLD were significantly more likely to be of the B cell type (100% vs. 89.8%, respectively; P=.05). PTLD in patients with early onset was less likely to involve the skin (P=.05) and spleen (P=.015), but more frequently complications of the respiratory tract (P=.002). Morphology of PTLD lesions was significantly different between the two groups with a priority for late-onset PTLD to represent non-Hodgkin lesions (P=.009). No difference was found between the two groups in survival (P=.237). One and five-year survival rates for early-onset PTLD patients were 65% and 46%, respectively; compared to 53% and 41%, respectively, for the late-onset PTLD.

CONCLUSION:

Due to a higher incidence of respiratory tract involvement in the early-onset PTLD patients and skin and spleen involvement in late-onset PTLD, we suggest that all heart/lung graft recipients should be evaluated for potential multiorgan disease based early or late presentation. Further multi-institutional prospective studies are needed to confirm our results.

Different patterns of cancer incidence among African American and Caucasian renal allograft recipients

BACKGROUND

Little data are available regarding cancer incidence in separately analyzed African American renal allograft recipients, with no study examining in detail the incidence and relative distribution of individual post-transplant malignancies versus those occurring in Caucasians.

METHODS

We compared the incidence of nonskin cancer occurring in 495 African Americans transplanted at our center from 1984 to 2007 and followed through June 2009 with that occurring in 11,155 patients in the Canadian Organ Replacement Registry transplanted from 1981 to 1998 and followed through December 1999, of which 97% were Caucasian.

RESULTS

Despite a shorter follow-up, the overall incidence of nonskin cancer, as well as that of prostate, renal cell, pancreatic, and esophageal cancer, was significantly higher in the African American group. Cancers of the prostate and pancreas comprised a significantly higher fraction of neoplasms occurring in the African American group, whereas lip cancer did so in the Canadian Organ Replacement Registry group.

CONCLUSION

In our pilot study, the overall incidence of nonskin cancers was higher in African American versus Caucasian renal allograft recipients, reflecting a significantly different relative distribution of cancer types that follows cancer incidence trends by race in the general population in several but not all cases. If verified in subsequent studies, these findings have important implications with regard to the need for transplant programs to tailor cancer education and pretransplant and post-transplant surveillance appropriately to the African American patient.

Post-transplant lymphoproliferative disorder involving the ovary as an initial manifestation: a case report

INTRODUCTION

Because the normal ovary is assumed to be devoid of lymphoid tissue, it is unusual for it to be an initial manifestation of malignant lymphoma. This case is the first report, to our knowledge, of post-transplant lymphoproliferative disorder involving the ovary as an initial manifestation.

CASE PRESENTATION

Twenty-nine weeks after a living renal transplantation, a 38-year-old Japanese female, whose ethnic origin was Asian, presented with abdominal pain and a chronic high fever. Computed tomography revealed a right ovarian tumor and liver metastases. The patient underwent oophrectomy based on the clinical diagnosis of liver metastasis from the primary ovarian tumor. The pathological diagnosis was Epstein-Barr Virus-associated post-transplant lymphoproliferative disorder. While ovarian malignant lymphoma has a poor prognosis, complete remission of liver involvement in this case was achieved only with a reduction of immunosuppressants.

CONCLUSION

Clinicians should remember that malignant lymphoma could initially involve the ovary, especially if the patient is immunosuppressed after transplantation therapy.

Diagnosis of post-transplant lymphoproliferative disorder in solid organ transplant recipients - BCSH and BTS Guidelines

A joint working group established by the Haemato-oncology subgroup of the British Committee for Standards in Haematology (BCSH) and the British Transplantation Society (BTS) has reviewed the available literature and made recommendations for the diagnosis and management of post-transplant lymphoproliferative disorder (PTLD) in adult recipients of solid organ transplants. This review details the risk factors predisposing to development, initial features and diagnosis. It is important that the risk of developing PTLD is considered when using post transplant immunosuppression and that the appropriate investigations are carried out when there are suspicions of the diagnosis. These must include tissue for histology and computed tomography scan to assess the extent of disease. These recommendations have been made primarily for adult patients, there have been some comments made with regard to paediatric practice.

Multicenter analysis of 80 solid organ transplantation recipients with post-transplantation lymphoproliferative disease: outcomes and prognostic factors in the modern era

PURPOSE Adult post-transplantation lymphoproliferative disease (PTLD) has a reported 3-year overall survival (OS) of 35% to 40%. The impact of rituximab on the outcome of PTLD is not well defined. METHODS We examined the clinical features and outcomes among a large cohort of solid organ transplantation (SOT) -related patients with PTLD who were recently treated at four Chicago institutions (from January 1998 to January 2008). Results Eighty patients with PTLD were identified who had a median SOT-to-PTLD time of 48 months (range, 1 to 216 months). All patients had reduction of immunosuppression as part of initial therapy, whereas 59 (74%) of 80 patients received concurrent first-line rituximab with or without chemotherapy. During 40-month median follow-up, 3-year progression-free survival (PFS) for all patients was 57%, and the 3-year overall survival (OS) rate was 62%. Patients who received rituximab-based therapy as part of initial treatment had 3-year PFS of 70% and OS 73% compared with 21% (P < .0001) and 33% (P = .0001), respectively, without rituximab. Notably, of all relapses, only 9% (4 of 34 patients) occurred beyond 12 months from PTLD diagnosis. On multivariate regression analysis, three factors were associated with progression and survival: CNS involvement (PFS, 4.70; P = .01; OS, 3.61; P = .04), bone marrow involvement (PFS, 2.95; P = .03; OS, 3.14; P = .03), and hypoalbuminemia (PFS, 2.96; P = .05; OS, 3.64; P = .04). Furthermore, a survival model by multivariate CART analysis that was based on number of adverse factors present (ie, 0, 1, > or = 2) was formed: 3-year PFS rates were 84%, 66%, 7%, respectively, and 3-year OS rates were 93%, 68%, 11%, respectively (P < .0001). CONCLUSION This large, multicenter, retrospective analysis suggests significantly improved PFS and OS associated with early rituximab-based treatment in PTLD. In addition, clinical factors at diagnosis identified patients with markedly divergent outcomes.

Immunosuppressive drugs in kidney transplantation: impact on patient survival, and incidence of cardiovascular disease, malignancy and infection

Renal transplant recipients have increased mortality rates when compared with the general population. The new immunosuppressive drugs have improved short-term patient survival up to 95% at 1-2 years, but these data have to be confirmed in long-term follow-up. Furthermore, no particular regimen has proved to be superior over others with regard to patient survival. Cardiovascular diseases are the most common cause of mortality in renal transplant recipients and while no immunosuppressive drug has been directly associated with cardiovascular events, immunosuppressive drugs have different impacts on traditional risk factors. Corticosteroids and ciclosporin are the agents with the most negative impact on weight gain, blood pressure and lipids. Tacrolimus increases the risk of new-onset diabetes mellitus. Sirolimus and everolimus have the most impact on risk factors for post-transplant hyperlipidaemia. Modifications in immunosuppression could improve the cardiovascular profile but there is little evidence regarding the beneficial effects of these changes on patient outcomes. Malignancies are also an increasing cause of mortality, overtaking cardiovascular disease in some series. Induction therapy, azathioprine and calcineurin inhibitors (CNIs) are probably the immunosuppressive agents most linked with post-transplant malignancies. Mycophenolate mofetil (MMF) has no negative impact on the incidence of malignancies. Target of rapamycin (mTOR) inhibitors have antioncogenic properties and they are associated with a lower incidence of malignancies. In addition, these agents have been recommended for use to decrease the dose or withdrawal of CNIs in patients with malignancies. Infections are still an important cause of morbidity and mortality in renal transplant recipients. Some immunosuppressive agents such as MMF increase the incidence of cytomegalovirus infection and the need for prophylactic measures in risk recipients. The use of potent immunosuppressive therapy has resulted in the appearance of BK virus nephropathy, which progresses to graft failure in a high percentage of patients. Although first associated with tacrolimus and MMF immunosuppression, recent data suggest that BK nephropathy appears with any kind of triple therapy. In conclusion, reducing risk factors for patient death should be a major target to improve outcomes after renal transplantation. Effort should be made to control cardiovascular diseases, malignancies and infections with improved use of immunosuppressive drugs. Preliminary results with belatacept suggest its safety and efficacy, and open new perspectives in the immunosuppression of de novo renal transplant recipients.

Immunosuppression and other risk factors for early and late non-Hodgkin lymphoma after kidney transplantation

Non-Hodgkin lymphoma (NHL) incidence is greatly increased after kidney transplantation. NHL risk was investigated in a nationwide cohort of 8164 kidney transplant recipients registered on the Australia and New Zealand Dialysis and Transplant Registry. NHL diagnoses were ascertained using linkage with national cancer registry records. Multivariate Poisson regression was used to compute incidence rate ratios (IRRs) with 95% confidence intervals (CIs) comparing risk by transplant function, and risk factors for early (< 2 years) and late (>/= 2 years) NHL during the first transplantation. NHL occurred in 133 patients. Incidence was strikingly lower after transplant failure and cessation of immunosuppression than during transplant function (IRR, 0.25; 95% CI, 0.08-0.80; P = .019). Early NHL (n = 27) was associated with Epstein-Barr virus (EBV) seronegativity at transplantation (IRR, 4.66; 95% CI, 2.10-10.36, P < .001) and receipt of T cell-depleting antibodies (IRR, 2.39; 95% CI, 1.08-5.30; P = .031). Late NHL (n = 79) was associated with increasing year of age (IRR, 1.02; 95% CI, 1.01-1.04; P = .006), increasing time since transplantation (P < .001), and current use of calcineurin inhibitors (IRR, 3.13; 95% CI, 1.53-6.39; P = .002). These findings support 2 mechanisms of lymphomagenesis, one predominantly of primary EBV infection in the context of intense immunosuppression, and another of dysregulated lymphoid proliferation in a prolonged immunosuppressed state.

Cancers after renal transplantation

For patients with end-stage kidney failure, kidney transplantation improves both their quality of life and overall life expectancy compared with dialysis, but it is not without adverse effects. Cancer is second to cardiovascular disease as one of the major causes of morbidity and mortality in renal transplant recipients. Prolonged use of modern immunosuppression, which leads to alteration of immune function and immune surveillance, is associated with increased cancer risk. There is now convincing evidence from observational studies and registry data to confirm a 3- to 5-fold increase in overall cancer incidence, with viral-related neoplasia incurring the greatest risk when compare with the general population. Despite the increased risk, little is known about the overall cancer prognosis, screening, treatment strategies, and effectiveness in this population. Cancers can recur, occur de novo, and be transmitted from donor organs posttransplantation. Uncertainties exist as to how modern immunosuppressive agents impact on cancer management and outcomes in these patients, with some agents such as calcineurin inhibitors and azathioprine, being more carcinogenic than others. The newer agents, proliferation signal/mammalian target of rapamycin inhibitors and mycophenolate mofitil, may have some antiproliferative and antitumor activities demonstrated in preclinical and clinical studies, but long-term well-powered trial data are needed to determine whether they are either protective or curative for cancers in renal transplant recipients. In this review, the incidence, etiology, prognosis, and potential approaches to cancer screening and management post-renal transplantation are discussed.

Lymphoma masquerading as a recurrent brachial artery aneurysm

Malignant lymphoma infiltrating the brachial artery in a renal transplant patient has not been documented previously. We report an angiodestructive B-cell lymphoma in a 64-year-old post-renal transplant recipient. Improved longevity post-transplantation has been associated with an increased incidence of cancer which means that we will be seeing such patients more frequently in the future.

[Lymphoproliferative disorders in kidney transplant recipients: incidence, clinical characteristics and outcome]

PURPOSE

The aim of this study was to determine the epidemiological and the clinical characteristics of post-transplant lymphoproliferative disease (PTLD) and to evaluate its impact on patients' and grafts' survival.

PATIENTS AND METHODS

Three hundred and sixteen adult kidney recipients, transplanted between June 1986 and May 2006, were included. The incidence rates were calculated by dividing the number of different events (PTLD, death and graft-loss) by the total duration of follow-up. The survival rates and the cumulated frequency of PTLD were calculated according to the actuarial method.

RESULTS

Seven recipients developed PTLD during a cumulated follow-up of 2202 years. The annual incidence was of 0.32% (95% CI : 0.30-0.34). It was of 0.81% (0.70-0.92) in recipients of kidneys from deceased donors, and of 0.25% (0.23-0.27) in patients transplanted from living donors (NS). The delay after transplantation for the diagnosis of PTLD ranged from 7.4 months to 7.7 years. PTLD was a B cell lymphoma in six cases and affected extra nodal sites in most of the cases. The treatment, comprising the cessation of immunosuppressive therapy in all cases, resulted in complete remission in four patients. Three patients died, representing an annual death rate of 6.1%, versus 2.8% in patients without PTLD (NS). The annual incidence of graft loss was 6.1% versus 3.2% among patients without PTLD (NS).

CONCLUSION

PTLD was observed in 2.2% of our patients, with an annual incidence of 0.32%. It resulted in a decrease of both patients' and grafts' survivals. Preventive measures, including the improvement of the monitoring of immunosuppressive drugs and the prevention of viral infections, should be considered to reduce the risk of PTLD.

Cancer after renal transplantation

PURPOSE OF REVIEW

Prolonged waiting times for renal transplantation, an increase in the average age of recipients, decreased acute rejection rates due to use of newer potent immunosuppressives and improving long-term transplant survival have raised concerns in the transplant community regarding posttransplant cancer. In view of the fact that transplant recipients are living longer, it is of paramount importance that we continue to translate discoveries at the bench to the bedside and document cancers in the posttransplant recipient registries. Analysis of data will help in optimizing patient management.

RECENT FINDINGS

Recent evidence indicates that sirolimus is associated with a decreased incidence of posttransplant de-novo cancer and remission of Kaposi's sarcoma and nonmelanoma skin cancer. Mycophenolate mofetil has been shown to have an antiproliferative activity against leukemia and lymphoma and an anti-tumor effect against colon and prostate cancer. Clinically it has been shown to be associated with a reduced incidence of cancers like posttransplant lymphoproliferative disorder.

SUMMARY

Appropriate selection of transplant candidates, pretransplant and posttransplant cancer surveillance and judicious evidence-based use of newer immunosuppressants may help reduce the incidence and improve the outcome of posttransplant cancer.

The separation of timescales in Bayesian survival modeling of the time-varying effect of a time-dependent exposure

In this paper, we apply flexible Bayesian survival analysis methods to investigate the risk of lymphoma associated with kidney transplantation among patients with end-stage renal disease. Of key interest is the potentially time-varying effect of a time-dependent exposure: transplant status. Bayesian modeling of the baseline hazard and the effect of transplant requires consideration of 2 timescales: time since study start and time since transplantation, respectively. Previous related work has not dealt with the separation of multiple timescales. Using a hierarchical model for the hazard function, both timescales are incorporated via conditionally independent stochastic processes; smoothing of each process is specified via intrinsic conditional Gaussian autoregressions. Features of the corresponding posterior distribution are evaluated from draws obtained via a Metropolis-Hastings-Green algorithm.

Evidence for genetic susceptibility towards development of posttransplant lymphoproliferative disorder in solid organ recipients

BACKGROUND

Posttransplant lymphoproliferative disorder (PTLD) is a life-threatening complication after organ transplantation. The identification of risk factors for PTLD development is important for disease management. It has been shown that cytokine gene polymorphisms are associated with lymphoma and Epstein-Barr virus (EBV)-associated diseases in nonimmunosuppressed patients. In the present case-control study, we analyzed the impact of -1082 interleukin (IL)-10, -308 tumor necrosis factor (TNF)-alpha, transforming growth factor (TGF)-beta1 (codon 10, 25), and +874 interferon (IFN)-gamma gene single-nucleotide polymorphisms on the late onset EBV-associated PTLD.

METHODS

Out of 1,765 solid organ recipients, 38 patients with late-onset EBV-associated PTLD and 408 matched solid organ recipients were selected and enrolled in the study. Single nucleotide polymorphisms (SNPs) for -1082IL-10, -308TNF-alpha, TGF-beta1 (codon 10, 25), and +874IFN-gamma genes were analyzed by a sequence specific primer polymerase chain reaction and were related to the PTLD development, and the disease course and outcome.

RESULTS

The TGF-beta1 (codon 25) GG genotype was detected more frequently in controls than in PTLD patients (odds ratio=0.34, 95% confidence interval: 0.17-0.69, P=0.0022). The frequency of -1082 IL-10 GG genotype was also significantly higher in controls than in PTLD patients (odds ratio=0.5, 95% confidence interval: 0.25-1.0, P=0.044). There were no associations between -308TNF-alpha, TGF-beta1 codon 10, and +874IFN-gamma SNPs and PTLD. Disease course and outcome were not associated with any cytokine SNPs.

CONCLUSIONS

Polymorphisms in two key anti-inflammatory cytokines, IL-10 and TGF-beta, are associated with susceptibility to EBV-associated PTLD, suggesting that a shift in pro-/anti-inflammatory response is involved in the pathogenesis of PTLD.

Is there a role for proliferation signal/mTOR inhibitors in the prevention and treatment of de novo malignancies after heart transplantation? Lessons learned from renal transplantation and oncology

With the development of new immunosuppressive agents, the majority of transplant recipients are surviving for over a decade, and malignancy has become a major burden on long-term survival. Reducing the incidence of post-transplant malignancies is especially important in heart transplantation where the risk of malignancies is higher than in other organ transplants. Everolimus and sirolimus, the proliferation signal inhibitors (PSIs) or mammalian target-of-rapamycin (mTOR) inhibitors, now provide new strategies for immunosuppression because of their proven efficacy that translates to a reduction in doses of calcineurin inhibitors needed to prevent acute rejection. In addition, the anti-proliferative effects of this class of drugs raise the possibility that they may be effective for reducing the risk of malignancies after solid-organ transplantation. Despite the paucity of direct clinical evidence for this effect in heart transplant patients, observations from renal transplant recipients suggest that the anti-proliferative actions of PSIs/mTOR inhibitors may also protect against malignancies in heart transplant recipients. This potential for an anti-cancer effect is further supported by the emerging data on the use of PSIs/mTOR inhibitors in non-transplant oncology patients. Reviewed in this article are the incidence rates of malignancies after solid-organ transplantation, and the evidence for anti-cancer effects of PSIs/mTOR inhibitors in renal transplant recipients and in non-transplant patients. Also discussed are the implications of these observational data for future studies on the reduction of malignancies after heart transplantation.

Complete Regression of Cutaneous B-Cell Lymphoma in a Renal Transplant Patient After Conversion From Cyclosporin to Sirolimus

Posttransplant lymphoproliferative disease remains a serious morbidity. Herein we have reported a case of complete regression of a biopsy-proven B-cell lymphoma that occurred in the posttransplant period. A 48-year-old man received a living donor renal transplant for end-stage renal disease due to undetermined etiology. His initial immunosuppression consisted of corticosteroid, mycophenolate mofetil, and cyclosporin. The patient developed severe pneumonia within the first 2 months after transplantation due to Acineotobacter, fungus, and cytomegalovirus infections. He experienced a complete recovery and was discharged for regional follow-up. Four months after discharge, he was referred again because of presence of two nodules on his trunk. A biopsy of the nodules revealed B-cell lymphoma. Cyclosporin was stopped and he was converted to sirolimus. The lesions regressed progressively and completely within 7 weeks. The patient remains well without clinical relapses at 19 months after conversion. Renal functions remained stable. We postulated that the antincoplastic properties of sirolimus may have played an active part in the positive outcome.

The emerging concept of antigen-driven lymphomas: epidemiology and treatment implications

PURPOSE OF REVIEW

Dramatic increases in the incidence of lymphomas worldwide have stimulated considerable efforts to identify factors that contribute to the etiology of this heterogeneous group of malignancies. The treatment and, ultimately, the prevention of lymphoma depend on our understanding of the complex interaction of exogenous agents with the molecular milieu which initiates and sustains a lymphoid malignancy. This review discusses the current evidence for the role of foreign or self antigens in the initiation of lymphomagenesis.

RECENT FINDINGS

Recent data have demonstrated an increased risk of lymphoma among individuals with chronic inflammatory conditions, persistent infections or immunodeficient states. Common to these clinical conditions is antigenic stimulation leading to an inflammatory cascade of cellular and cytokine reactions that may tax the host immune response, provoke tissue injury and eventually result in lymphoid neoplasia.

SUMMARY

Efforts to detect and suppress chronic, antigen-driven inflammation have suggested that neoplastic progression may often be interrupted and controlled. Elucidation of the etiologic mechanisms critical to the survival of these malignancies would provide promising alternatives for the prevention and treatment of some lymphomas.